(1) Field of the Invention
This invention relates to a radiometric scanner and an incubator incorporating the scanner, useful for detection of the chemical state of a plurality of substrates. In a preferred embodiment the substrates are scanned optically to provide a quantitative clinical analysis of blood components.
(2) State of the Prior Art
Radiometric scanner cover a wide range of the electromagnetic spectrum. Optical scanners have been used to examine by light the contents of a substrate, such as a printed page. Although such scanners commonly move continuously across the substrate, they are not so limited and include those that obtain a reading without relative motion between the substrate and the sensor.
Some optical scanners have been designed for projecting characters from a single support station or platform using a light source and a screen, both of which are positioned on the axis of rotation of a lens system which creates sequential light beams, the lens system rotating with respect to the platform. An example is shown in U.S. Pat. No. 3,591,249. Or alternatively the substrate being read can be linearly moved through a plurality of light beams that are discontinuously formed by a lens and mirror system rotating about an axis on which the light source, receptor, and substrate support are positioned, as shown in U.S. Pat. No. 3,345,460. Such devices are not intended for use, however, in incubators.
Some conventional incubators useful for radiometrically measuring the state of a substrate, usually in liquid form, for clinical analysis generally have a plurality of stations for the substrates, often mounted for rotation about an axis, a temperature control system including a heater, and a radiometer of some type, such as a reflectometer, designed to selectively scan each of the stations. A relatively simple example of such an incubator is shown in U.S. Pat. No. 3,616,264, whereas U.S. Pat. Nos. 3,533,744; 3,756,920; 3,758,274; 3,788,816 and 3,790,346 illustrate more complex apparatus. In U.S. Pat. No. 3,533,744, flat substrates using liquid analysis are positioned tangential to a surface of revolution which they trace as they are rotated about a pair of axes formed by a conveyor system. In this art, however, no provision is made for mounting the optics of the scanner for movement, particularly for rotation, apart from the rotation of the platforms. That is, the optics are not independently mounted for rotation. As a result, the apparatus must examine in sequence each station that comes into position. However, many of the analytes of interest are desirably analyzed for a rate of reaction, with each analyte having a different rate. Problems exist in reading such rate reactions by sequentially scanning each station. A system which rotates only the substrate stations, but not the optics, necessitates a much longer search time and thus less data is available for rate analysis within a given time.
Reflectometers have also scanned the periphery of rotating stations having bacteria cultures, there being however no heaters provided as in incubators used in clinical analysis. An example is shown in U.s. Pat. No. 3,776,817. Independent motion of the optics apart from that of the stations is not provided in such devices, so that the search capability is limited.
Patents relating only to the general background of optical scanners include U.S. Pat. Nos. 3,508,065; 3,700,911 and 3,778,129.
(3) Related Applications
Commonly owned U.S. application Ser. No. 751,872 entitled "Method and Apparatus for Chemical Analysis," filed in the name of C. Glover at al on Dec. 17, 1976, now abandoned, discloses apparatus for analyzing dried substrates, including a rotating incubator.
U.S. Pat. No. 4,067,694 issued on Jan. 10, 1978 on commonly owned U.S. application Ser. No. 751,869 entitled "Loading and Unloading Mechanism for Continuously Rotating Container," filed in the name of R. Blakely et al on Dec. 17, 1976, discloses a feeding mechanism for a continuously rotating processor such as an incubator.